The warnings below ONLY apply to the PTFE if it is in the MELT ZONE. If it is just being used for it’s tighter tolerances then you do not need to worry about the PTFE off-gassing as it is not exposed to the nozzle heat.
PTFE is a polymer that has high heat resistance and low friction which makes it a great material for bowden tubing applications. However when used in the melt zone of your hotend you need to be aware that at temperatures up to 250C are generally considered safe. However past this the PTFE can emit what is referred to as off-gassing. This is not typically harmful to humans but small animals, especially birds can have their respiratory systems harmed. We recommend staying under 275C as higher than that has been tested by us but can reduce the life span of the tubing in the melt zone and cause more off-gassing. If you want to regularly print over 275C we recommend going with an all metal hotend.
You can use the ToughTubing and other high temp brands in the melt zone but make sure you take the proper precautions. Many machines on the market come with low quality PTFE already in the melt zone and they will emit gasses as they are heated. There is nothing wrong with using our tubing or others in the melt zone as long as you take the proper precautions to minimize the off-gassing. In addition to that the material you print with may also off-gas as it is printed.
- Run your printer in a well ventilated area
- Keep it away from children and pets
- Especially birds as their respiratory systems are VERY sensitive to harmful gasses.
- In a classroom environment stick with PLA and stay away from high temp materials (even if you aren’t using PTFE in the melt zone)
- Always run the printer ATTENDED
If you want more information on PTFE and off-gassing the folks over at Capricorn have put together a nice write up on their site here with some links to scientific study articles: https://www.captubes.com/safety.html
You can also download the MSDS sheet for our PTFE tubing here: https://www.th3dstudio.com/downloads/TH3D_ToughTube_MSDS.pdf
Capricorn is NOT affiliated with TH3D, we are just linking to their site to share more information.